The invention relates to an operating system for elevator doors consisting of a magnet movably mounted on a car door, the magnetic field of the magnet acting on a magnetizable operating cam mounted on a hoistway door.
From patent specification U.S. Pat. No. 5,487,449 an operating device has become known by means of which the car door is magnetically coupled with the hoistway door when the car door and hoistway door are opened and closed. The magnetic field of an electromagnet or permanent magnet mounted on the car door acts on a coupler mounted on the hoistway door, as a result of which the doors are coupled by magnetic force, and opened and closed together by means of a door drive. To make the coupling smoother, rollers which can be swiveled are mounted on the magnet, the magnetic force acting against spring forces created by springs mounted on the rollers.
From patent specification U.S. Pat. No. 3,913,270 an operating device has become known which has an electromagnet mounted on the car door in a vertically movable manner. Two guides running in a vertical direction give the electromagnet a limited amount of freedom to move in the vertical direction, the electromagnet being held in the correct position by means of springs. When the car door couples with the hoistway door, the electromagnet acts on an operating rail, which is mounted on the hoistway door in a swiveling manner, the operating rail thereby being drawn toward the electromagnet. When decoupling takes place, the electromagnet is switched off. When this happens, the operating rail, which is supported by swivel arms, is released from the electromagnet and swivels downwards.
A disadvantage of the known device is that the tolerances inherent in the elevator system cannot be sufficiently corrected by the operating device, and there is therefore a danger that the operating device collides with either the hoistway door sill, or parts of the hoistway door lock, while the elevator is in operation, which can cause faults in the elevator and damage to parts of the installation.